Since Young and Dukes are not on the major league roster, I did not think they needed to clear waivers....and Tampa would be able to claim the Marlin players with their waiver priority. Not sure if I'm right though.

It doesn't matter what Tampa's waiver priority would be. IIRC, any Marlins players would have to go unclaimed by every team in the NL before they would be available to teams in the AL. No way that would happen.